This power control from a 1968 Motorola manual shows how to use a contemporary diac as a zero-crossing detector. The SCR is of the type depending on the power of the load.
The components of this circuit are still common today. The circuit is from a 1967 publication by...
This analog TV circuit can be used on a small transmitter. The circuit is from an 80's American...
We found this circuit in a 1976 documentation. The FET can be BF245 or MPF102 and the power supply...